JP2005069528A - Heat accumulation type heating system, and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat accumulation type heating system, without generating heat accumulation shortage or excess heat accumulation even when there is quick change in outside air temperature. <P>SOLUTION: This heat accumulation type heating system 10 is provided with an electric heater 11, heat accumulation material 12 heated by the electric heater 11 to accumulate heat, and an energization control part 13 to conduct energization control to the electric heater 11. The energization control part 13 determines a corrected temperature rise pattern corrected based on a reference temperature rise pattern of the heat accumulation material 12 in accordance with aging when the electric heater 11 is continuously energized, so that temperature rising speed is smaller at each temperature, and conducts on/off control for energization to the electric heater 11, so that the heat accumulation material 12 is heated in the corrected temperature rise pattern. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat storage heating system including an electric heater and a heat storage material that stores heat by being heated by the electric heater and a control method thereof.

  A heat storage type floor heating system generally includes an electric heater, a heat storage structure floor (heat storage material), a temperature sensor for measuring the floor temperature, and an energization control unit having a timer function. Electricity is passed through an electric heater using cheap midnight power to store heat in the heat storage material, and heat is released during the day to warm the room.

  For example, Patent Document 1 calculates the sum of the non-energization times of the regenerative electric floor heating system, and in the subsequent heat storage operation, the heat storage operation start time is set for a predetermined time determined based on the calculated sum of the non-energization times. It is disclosed to delay. And according to this, when performing a thermal storage operation so that the temperature of the thermal storage type electric floor heating system becomes a set temperature, it is described that the thermal storage operation start time can be set accurately.

  Patent Document 2 compares the underfloor temperature and the set underfloor temperature from the beginning of the heat storage operation time to the start of the heat storage operation, and when the underfloor temperature has decreased to the set underfloor temperature before the heat storage operation start time, It is disclosed that the time at which the underfloor temperature becomes equal to the set underfloor temperature is predicted from the temperature gradient, and the heat storage operation start time is advanced by a time corresponding to the time from the predicted time to the heat storage operation start time. And according to this, when performing the heat storage operation so that the temperature of the heat storage type electric floor heating system becomes the set temperature, it is described that the heat storage operation start time can be accurately set according to the heat radiation amount. .

  By the way, even though midnight power is inexpensive, it is desired to operate the regenerative floor heating system efficiently while avoiding unnecessary power consumption as much as possible. Ideally, in the midnight power supply time zone, the heat storage for the amount of heat required for the next day should be completed just when the midnight power supply time ends.

Patent Document 3 predicts the amount of heat necessary for the heat radiation operation of the next day from the temperature of the day of the day or the temperature of the part that changes corresponding to the outside temperature, and a heater required to store the necessary amount of heat based on this prediction. It is disclosed that an energization time is determined, a heat storage operation start time is obtained by calculating backward from a predetermined heat storage operation end time, and the heat storage operation start time is made variable according to the outside air temperature. And according to this, it is described that only the amount of heat necessary for heating is stored in the heat storage material, and the amount of stored heat is used up at the time of heating, thereby enabling efficient operation of the heat storage electric floor heating device.
JP 2000-81219 A JP 2000-81220 A JP 2001-90969 A

  According to the technique described in Patent Document 3, since the heater energization start time is predicted mainly from the average value of past data, an optimal heat storage amount is ensured when the outside air temperature is stabilized to some extent. can do.

  However, if the outside air temperature changes suddenly when the heater is energized, heat storage to the heat storage material may be insufficient or excessive. For example, it is assumed that a certain amount of heat storage amount is required for the next day's floor heating and the heater is energized at a predetermined time to start heat storage. If the outside air temperature drops rapidly at this time, even if the heat storage material is heated, the temperature does not rise sufficiently, and the energization time ends without the amount of heat actually required the next day being accumulated, resulting in insufficient heat storage. Because of it, you will feel cold. In particular, at the turn of the season, such as autumn to winter, winter to spring, etc., the temperature changes with a short period on average, but changes greatly on average. There are many cases where this is not possible.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a regenerative heating system and a control method thereof that do not cause shortage of heat storage or excessive heat storage even when there is a sudden change in outside air temperature. It is to provide.

The regenerative heating system according to the present invention that achieves the above object is as follows.
An electric heater;
A heat storage material that stores heat by being heated by the electric heater;
An energization control unit that controls energization of the electric heater;
With
The energization control unit obtains a corrected temperature increase pattern obtained by correcting the time-dependent reference temperature increase pattern of the heat storage material when the electric heater is continuously energized so that the temperature increase rate at each temperature is small, and the correction The energization of the electric heater is on / off controlled so that the temperature of the heat storage material is increased according to the temperature increase pattern.

  According to said structure, it has a time margin rather than the case where it heats up a thermal storage material according to a reference | standard temperature rising pattern. Therefore, in the case of a standard in which there is no change in the outside air temperature, heat is stored until the electric heater is turned on and off and the heat storage material reaches a predetermined temperature. When the outside air temperature rapidly decreases, in order to increase the temperature of the heat storage material in accordance with the corrected temperature increase pattern, more heat is required than in the standard case. Heat is stored until the on-time is increased, thereby supplementing the heating time and the heat storage material reaches a predetermined temperature. Also, when the outside air temperature rises sharply, it takes less heat than the standard case to raise the temperature of the heat storage material according to the corrected temperature rise pattern. The heat is stored until the heat storage material reaches a predetermined temperature while the heating time is shortened. In this way, even when the outside air temperature suddenly decreases or rises, the on-time of the electric heater expands and contracts, thereby preventing insufficient heat storage and excessive heat storage.

  In such a heat storage type heating system, the time until the heat storage material reaches the target temperature is predicted from the corrected temperature increase pattern, and the time is calculated backward from a predetermined heat storage end time, for example, the midnight power supply end time. The on / off control of the electric heater may be started from the time. When heat storage of the heat storage material is started at the same time as the midnight power supply start time, if the heat storage is completed before the midnight power supply end time, extra power to maintain the heat storage until the heat is released must be used. Don't be. However, with the above configuration, heat storage is completed at a predetermined heat storage end time such as the late-night power supply end time, so that unnecessary power consumption is prevented.

  Rather than fixing the data of the reference heating pattern, it is preferable to make corrections that reflect changes in the climate. However, since the heat storage to the daily heat storage material is performed according to the corrected temperature increase pattern, the data of the reference temperature increase pattern cannot be directly acquired. Therefore, from the past actual temperature rise pattern of the heat storage material, the portion that raises the temperature corresponding to the temperature decreased at the time of turning off of the portion when the electric heater is turned off and the portion when the electric heater is turned on is removed and continued. It is conceivable to substitute the above as a reference temperature rising pattern.

  The reference temperature rise pattern data may be simply obtained from the previous day, but it may be unique data, so in order to perform highly reliable control, the past of the heat storage material is used. It is preferable that an average of the plurality of temperature rising patterns is a reference temperature rising pattern.

  The correction method from the reference temperature increase pattern to the corrected temperature increase pattern is not particularly limited, and various methods are conceivable. For example, a predetermined temperature increase rate at each temperature of the heat storage material in the reference temperature increase pattern is determined. A product obtained by multiplying a constant or a variable can be used as a temperature increase rate at a temperature corresponding to the heat storage material in the corrected temperature increase pattern.

  The regenerative heating system according to the present invention as described above is typically used for floor heating applications.

  As described above, according to the present invention, since there is a time margin compared with the case where the temperature of the heat storage material is increased according to the reference temperature increase pattern, even if the outside air temperature is suddenly decreased or increased, the electric heater By expanding and contracting the on-time, it is possible to prevent the occurrence of insufficient heat storage or excessive heat storage.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a configuration of a regenerative floor heating system 10 according to an embodiment of the present invention.

  The heat storage type floor heating system 10 includes an electric heater 11, a heat storage material 12, and an energization control unit 13. In the heat storage type floor heating system 10, the energization control unit 13 performs energization control of the electric heater 11. The electric heater 11 heats and stores the heat storage material 12 when energized. Regardless of whether the electric heater 11 is energized or not energized, the heat storage material 12 always radiates the stored heat. And floor heating is performed by the heat dissipation of such a heat storage material 12. Note that a temperature sensor (not shown) for detecting the temperature of the heat storage material 12 is provided so that temperature information of the heat storage material 12 is always input to the energization control unit 13.

  For example, a latent heat and sensible heat storage type floor structure can be configured by the heat storage type floor heating system 10.

  FIG. 2 shows such a latent heat and sensible heat storage type floor structure.

  In this floor structure, a heat insulating material layer 22 and a mortar layer 24 in which a wire mesh 23 is embedded are sequentially laminated on a concrete slab 21, and a floor finishing material 25 is provided thereon. The heat storage material 12 is laid between the heat insulating material layer 22 and the mortar layer 24, and the electric heater 11 including a heating cable is wired on the heat storage material 12. Further, the wiring 14 provided through the concrete slab 21 and the heat insulating material layer 22 is connected to the electric heater 11. Of course, this heat storage type floor heating system 10 may constitute a latent heat storage type floor structure or a sensible heat storage type floor structure.

  The heat storage type floor heating system 10 is configured to energize the electric heater 11 using late-night power with a low electricity bill, thereby storing heat in the heat storage material 12. The control is performed by the energization control unit 13. The details of the control will be described below.

-Reference heating pattern determination step-
A reference temperature increase pattern over time of the heat storage material 12 when the electric heater 11 is continuously energized is determined. That is, a relationship graph (hereinafter referred to as “temperature rise curve”) between the energization time when the electric heater 11 is continuously energized and the temperature of the heat storage material 12 is determined.

  At this time, as the temperature increase curve, as shown in FIG. 3, for example, one fixed for each period or one obtained on the previous day may be adopted. However, the fixed temperature rise curve cannot cope with a case where the abnormal climate continues for a long period of time, and the temperature rise curve obtained on the previous day cannot cope with the case where the previous day is abnormal weather. There is a risk that the reliability is lowered. Therefore, in order to perform highly reliable control, it is preferable to employ an average temperature rise curve obtained by averaging a plurality of temperature rise curves obtained in the past few days. The average temperature rise curve can be obtained as follows.

  First, as shown in FIG. 4, a temperature rise curve as shown in FIG. 3 is divided into ΔTa−b (= 1 ° C.) (a and b are temperatures, ba = 1 ° C.) in a range of 29 to 45 ° C. The temperature rise curve is linearly approximated for each temperature range of ΔTa-b (= 1 ° C.) and the time Δta-b (a, b is the temperature, ba) required for the temperature to rise by ΔTa-b (= 1 ° C.) = 1 ° C). The rate of temperature rise in each temperature range is ΔTa−b / Δta−b of the slope of the straight line. For example, when the range of 44 to 45 ° C. is taken as an example, as shown in FIG. 5A, a time of Δt 44-45 is required for the temperature rise of ΔT 44-45 = 1 ° C. Accordingly, the rate of temperature rise in this range is 1 / Δt44-45. Although the time of 29 ° C. which is the starting point is unknown, as shown in FIG. 5B, the time Δt 29-30 required for the temperature rise of ΔT 29-30 = 1 ° C. is obtained by extrapolating a straight line. Can be requested. And the same process is performed about the temperature rise curve for the past several days.

Subsequently, for each temperature range of ΔTa−b (= 1 ° C.), Δta−b for the past several days and a temperature rise curve that is linearly approximated are averaged. For example, when averaging Δta-b for the past two days, taking the range of 44 to 45 ° C as an example, aveΔt44-45 is calculated by adding Δt44-45 (previous day) and Δt44-45 (previous day). The sum is divided by 2. That means
aveΔt44-45 = (Δt44-45 (previous day) + Δt44-45 (previous day)) / 2
It becomes. In addition, the average of the temperature rise curves approximated by a straight line is as shown in FIG. ) And a line segment having an intermediate temperature increase rate (slope).

  And as shown in FIG. 7, the average temperature rise curve is obtained by connecting continuously the average of the temperature rise curve which carried out the linear approximation in each temperature range in the range of 29-45 degreeC. In addition, this average temperature rise curve connects the line segments, and is not strictly a curve.

-Corrected heating pattern calculation step-
A corrected temperature rising pattern corrected so that the temperature rising rate at each temperature of the heat storage material 12 is smaller than the reference temperature rising pattern is obtained.

  First, the temperature rise curve or the average temperature rise curve is divided into ΔTa−b (= 1 ° C.) (a and b are temperatures, ba = 1 ° C.) in the range of 29 to 45 ° C., and each ΔTa−b (= The temperature range of 1 ° C. is linearly approximated, and the time Δta-b (a and b are temperatures, ba = 1 ° C.) required for the temperature to rise by ΔTa-b (= 1 ° C.) is obtained. Again, the rate of temperature rise in each temperature range is ΔTa−b / Δta−b of the slope of the straight line. For example, when an average temperature rise curve is used, taking the range of 44 to 45 ° C. as an example, it takes aveΔt 44-45 time for temperature rise of ΔT 44 -45 = 1 ° C. Therefore, the rate of temperature rise in this range is 1 / aveΔt44-45.

  Subsequently, with respect to each temperature range of ΔTa−b (= 1 ° C.), Δta−b is multiplied by a constant or a variable to extend the time, and based on this, the average temperature rise curve is converted. In other words, this means that, for each temperature range of ΔTa−b (= 1 ° C.), the rate of temperature increase is multiplied by a constant or a variable (a constant multiplied by Δta−b or the inverse of the variable) to decelerate. For example, using the average temperature rise curve, when Δta-b is multiplied by a constant K (for example, 1.1) for time extension, taking the range of 44 to 45 ° C. as an example, as shown in FIG. aveΔt44-45 is extended to K · aveΔt44-45 (K> 1) over time. Accordingly, the temperature increase rate in this range is reduced to 1 / (K · aveΔt44-45). The average temperature rise curve (line segment) is converted into a gentle one with a slope of 1 / (K · aveΔt44-45).

  Then, as shown in FIG. 9, a line segment obtained by converting the average temperature rise curve (line segment) is continuously connected in a range of 29 to 45 ° C., thereby forming a temperature increase target curve, that is, a corrected temperature increase pattern. obtain. Note that this temperature increase target curve is also a line segment connected and is not strictly a curve.

-Thermal storage start time calculation step-
The time until the heat storage material 12 reaches the target temperature is predicted from the corrected temperature increase pattern, and a time obtained by reversely calculating the time from the predetermined heat storage end time, that is, the midnight power supply end time, is calculated as the heat storage start time.

  Specifically, using the above example, when the target temperature is 45 ° C., the time for the heat storage material 12 to rise from 29 ° C. to 45 ° C. is ΣK · aveΔta−b (= K · aveΔt) It only takes. The time when the above time is calculated backward from the midnight power supply end time (for example, 7:00 am) is the heat storage start time.

  When heat storage of the heat storage material 12 is started at the same time as the midnight power supply start time, if the heat storage is completed before the midnight power supply end time, extra power for maintaining the heat storage until the heat is released must be used. However, in this way, heat storage is started by calculating backward from the end of midnight power supply, and heat storage is completed at the end of midnight power supply, so that unnecessary power consumption is prevented. .

-Thermal storage step-
When the heat storage start time comes, the energization to the electric heater 11 is controlled to be turned on / off so that the heat storage material 12 is heated in the corrected temperature rising pattern.

  As shown by broken lines in FIGS. 10 (a) and 10 (b), when the heat storage material is heated with a reference temperature increase curve, that is, with a reference temperature increase pattern, the electric heater is energized continuously. In addition, the temperature rise pattern of the heat storage material is a smooth curve that substantially matches the reference temperature rise pattern. In contrast, in the regenerative floor heating system 10, as shown by solid lines in FIGS. 10 (a) and 10 (b), the rate of temperature rise is decelerated from the above case, and heat is stored with a time margin. Since the electric heater 11 is energized by the on / off control, the energization is intermittent, and the temperature of the heat storage material 12 decreases when the power is off. Therefore, the temperature increase pattern of the heat storage material 12 is a corrected temperature increase pattern. However, it does not become a smooth curve. For example, in the above example, when the constant K = 1.1, 90% from the start to the end of energization is energization on and 10% is energization off. However, this is a case where there is no change in the outside air temperature. On the other hand, when the outside air temperature rapidly decreases, in order to raise the temperature of the heat storage material 12 according to the corrected temperature rising pattern, a larger amount of heat is required than when there is no change in the outside air temperature. 100% is energized and heat is stored until the heating time is compensated and the heat storage material 12 reaches a predetermined temperature. Further, when the outside air temperature rises rapidly, heating the heat storage material 12 in accordance with the corrected temperature raising pattern requires less heat than when there is no change in the outside air temperature, so 70 to 80% is energized. When ON, 20 to 30% is energized and heat is stored until the heat storage material 12 reaches a predetermined temperature while the heating time is reduced. In this way, even if the outdoor temperature suddenly decreases or rises, the on-time of the electric heater 11 is expanded and contracted, so that insufficient heat storage or excessive heat storage is prevented.

  By the way, in this heat storage type floor heating system 10, the heat storage material 12 is not heated by continuously energizing the electric heater 11, and the heat storage to the heat storage material 12 is performed according to the corrected temperature increase pattern. Data cannot be obtained directly every day. Therefore, in this regenerative floor heating system 10, as shown in FIG. 11, the portion (b) when the electric heater 11 is turned off and the electric heater 11 when the electric heater 11 is turned on from the temperature rise pattern (A) of the actual heat storage material 12. Of the portion, the portion (c) where the temperature corresponding to the temperature lowered at the time of OFF is removed is removed and continued, and the reference temperature rising pattern is used instead.

  In the case of a conventional system in which an electric heater is continuously energized, on / off control of the electric heater is performed at a high temperature after reaching the target temperature, and wasteful heat is generated by dissipating heat at the time of turning off. In this heat storage type floor heating system 10, since the electric heater 11 is controlled to be turned on and off when heat is stored in the heat storage material 12, wasteful heat is generated by dissipating heat at the time of off, but such heat dissipation is low until reaching the target temperature. It occurs in the temperature range. Therefore, the amount of heat that is wasted is not as great as the conventional one.

  As described above, the present invention is useful for a heat storage type heating system including an electric heater and a heat storage material that stores heat by being heated by the electric heater.

It is a block diagram which shows the structure of the thermal storage type floor heating system which concerns on embodiment of this invention. It is sectional drawing which shows an example of the floor structure to which the thermal storage type floor heating system which concerns on embodiment of this invention was applied. It is a graph which shows the temperature rise curve of a thermal storage material. It is a graph for obtaining an average temperature rise curve from the temperature rise curve of a heat storage material. It is explanatory drawing for calculating | requiring time (DELTA) ta-b required for temperature to raise (DELTA) Ta-b. It is explanatory drawing for obtaining an average temperature rise curve from the temperature rise curve of a thermal storage material. It is a graph which shows the average temperature rise curve of a thermal storage material. It is explanatory drawing which shows the time expansion | extension of ave (DELTA) t44-45. It is a graph which shows a temperature increase target curve. It is a graph which shows the temperature rising pattern of the thermal storage material at the time of thermal storage. It is explanatory drawing for obtaining a reference | standard temperature rising pattern from the temperature rising pattern of an actual heat storage material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Thermal storage type floor heating system 11 Electric heater 12 Thermal storage material 13 Current supply control part 14 Wiring 21 Concrete slab 22 Heat insulating material layer 23 Wire mesh 24 Mortar layer 25 Floor finish material

Claims (7)

An electric heater;
A heat storage material that stores heat by being heated by the electric heater;
An energization control unit that controls energization of the electric heater;
With
The energization control unit obtains a corrected temperature increase pattern obtained by correcting the time-dependent reference temperature increase pattern of the heat storage material when the electric heater is continuously energized so that the temperature increase rate at each temperature is small, and the correction A regenerative heating system that performs on / off control of energization of the electric heater so that the heat storage material is heated in a temperature rising pattern. In the regenerative heating system according to claim 1,
The energization control unit predicts a time until the heat storage material reaches a target temperature from the corrected temperature increase pattern, and starts on / off control of the electric heater from a time obtained by calculating back the time from a predetermined heat storage end time. , Regenerative heating system. In the regenerative heating system according to claim 1,
The energization control unit removes, from the past corrected temperature increase pattern, a portion that raises the temperature corresponding to a temperature that has decreased when the electric heater is turned off from a portion when the electric heater is turned off and a portion when the electric heater is turned on. A regenerative heating system that uses a continuous pattern as a reference heating pattern. In the regenerative heating system according to claim 1,
The energization control unit is a heat storage type heating system in which an average of a plurality of past temperature increase patterns of the heat storage material is used as a reference temperature increase pattern. In the regenerative heating system according to claim 1,
The energization control unit is a heat storage unit that uses a temperature increase rate at each temperature in the reference temperature increase pattern multiplied by a predetermined constant or variable as a temperature increase rate at a temperature corresponding to the heat storage material in the corrected temperature increase pattern. Heating system. In the regenerative heating system according to claim 1,
A regenerative heating system used for floor heating applications. A control method for a regenerative heating system comprising an electric heater and a heat storage material that is heated and stored by the electric heater,
Determining a reference temperature rise pattern over time of the heat storage material when the electric heater is energized continuously;
Obtaining a corrected temperature increase pattern obtained by correcting the reference temperature increase pattern so that the temperature increase rate at each temperature is small;
On / off controlling the energization of the electric heater so that the heat storage material is heated in the corrected temperature rising pattern;
A control method for a regenerative heating system.

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